Saturday, April 17, 2010
The largest eruptive prominence observed in years blasted into space (April 13, 2010) and SOHO was lucky enough to have caught a key moment of it. As observed in extreme UV light, the plasma cloud was caught about mid-step in its liftoff above the Sun's surface. (Ground-based observers says the eruption took about two hours.) It was not obvious what triggered the breakaway, but it may have been associated with a coronal mass ejection (CME).
Prominences are cooler clouds of gases that hover above the Sun, tethered there by magnetic forces. Occasionally, as seen here, they break free and blast into space.
The bright edge of the expanding cloud is distinctly displayed in the LASCO C2 field of view in which the Sun (represented by the white circle) is blocked by a central disk. The video clip shows it dispersing over about an eight hours. The expanding prominence is the bright stuff in the position of the "filament" of the broader and fainter CME "light bulb."
Posted by Helge at 9:59 PM